RFR: 8025692: Add trace to find out what methods are used at runtime.

[Yumin Qi]

Ping! Any comments please.

On 6/4/2015 8:12 PM, Yumin Qi wrote:
> HI, All
>
>   After several round of codereviews and discussion, now the second 
> version is at:
>   http://cr.openjdk.java.net/~minqi/8025692/webrev02/
>
>   The flag names changed:
>
>   TraceMethodUsge => LogTouchedMethods
>   PrintMethodUsageAtExit => PrintTouchedMethodsAtExit
>
>   The two flags now are diagnostic flags.
>
>    Also similar, there changed in related variable names.
>    Also fixed a flaw which is not found during last round of review: 
> append new TouchedMethodRecord to end of hash bucket list.
>
>   Make change to interpreter method entry  generation(for both native 
> and normal) to enable build_method_counter called. This is necessary 
> since if run -Xint, the call will be skipped so our code will be 
> skipped so no logging for touched methods.
>
>   Added test case for jcmd: jcmd <pid> VM.print_touched_methods.
>
>   Tests: JPRT, aurora default test suites (in progress).
>
> Thanks
> Yumin
>
>
> On 3/26/2015 7:34 PM, Yumin Qi wrote:
>> Please review:
>>
>> bug: https://bugs.openjdk.java.net/browse/JDK-8025692
>> webrev: http://cr.openjdk.java.net/~minqi/8025692/webrev01/
>>
>> Summary: Add two flags to help list all java methods called in 
>> runtime, this is also in product and can help CDS to rearrange 
>> methods in shared archive to avoid loading infrequent methods into 
>> memory.
>>
>> Tests: vm.runtime.quick.testlist, JPRT
>>
>>
>> Thanks
>> Yumin
>>
>>
>